Quorum sensing (QS), a well-established phenomenon in microorganisms, involves the communication between cells through chemical signals, which is dependent on cell density. Extensive research has been conducted on this microbial ability, encompassing the early stages of understanding QS to the latest advancements in the identification and characterization of its mechanisms. This minireview comprehensively examines the role of QS in various aspects, including biofilm formation, virulence in pathogenic bacteria such as Helicobacter pylori and Pseudomonas sp., as well as its influence on biogeochemical cycling in deep-sea environments. Furthermore, future progress in the field will be achieved by combining state-of-the-art methods for observing QS in the deep sea with a deeper understanding of the underlying processes, which will facilitate the engineering of microorganisms for improved degradation of persistent environmental pollutants and other biotechnological applications.

ABSTRACT Surfactants are a broad category of tensio-active biomolecules with multifunctional properties applications in diverse industrial sectors and processes. Surfactants are produced synthetically and biologically. The biologically derived surfactants (biosurfactants) are produced from microorganisms with Pseudomonas aeruginosa, Bacillus subtilis Candida albicans and Acinetobacter calcoaceticus as dominant species. Rhamnolipids, sophorolipids, mannosylerithritol lipids, surfactin, and emulsan are well known in terms of their biotechnological applications. Biosurfactants can compete with the synthetic surfactants in terms of performance with established advantages over the synthetic ones including eco-friendliness, biodegradability, low toxicity, and stability over a wide variability of environmental factors. However, at present, the synthetic surfactants are a preferred option in different industrial applications, because of their availability in commercial quantities, unlike the biosurfactants. Usage of synthetic surfactants introduce new species of recalcitrant pollutants to the environment and lead to undesired results where a wrong selection of surfactants is made. Substituting synthetic surfactants with biosurfactants resolves these drawbacks, thus, interest has been intensified in biosurfactant applications in a wide range of industries hitherto considered as experimental fields. This review, therefore, intends to offer an overview of diverse applications where biosurfactants have found useful, with emphases in petroleum biotechnology, environmental remediation and in the agriculture sector. Application of biosurfactant in these settings would lead to industrial growth and environmental sustainability.